Care
The Five-lined Cardinalfish is known from reef flats, lagoons, and seaward reefs to depths of 40m (131ft). This nocturnal species may be observed singly or in groups, taking shelter in dark crevices, under ledges and branched corals, and amongst the spines of the long-spined sea urchin
Diadema setosum. At night, these fish feed on crustaceans, gastropods, and small fishes. The aquarium should be aquascaped with plenty of live rock, creating lots of shady hidey holes and overhangs (do ensure these are secure). The more places of safety available to these fish, the more you will see them out in the open, as they will learn that they can quickly retreat if necessary. As this is a semi-aggressive cardinalfish, it is best to keep only a single specimen unless the aquarium is very spacious (over 6ft in length); in larger quarters, a group of 6 or more could be kept together if introduced simultaneously when juveniles. When keeping multiple specimens, good sized groups are a must, as when kept in small numbers, the smallest/weakest individual will be picked off until only one is left - maintained in larger numbers, any aggression is spread out through the group and no one fish should receive continual harassment. Tankmates should be of similar size, and the cardinalfish introduced last to give more docile species a chance to establish themselves first. Five-lined Cardinalfish are best kept in a reef situation, but not with any small ornamental shrimps, crabs, or snails. Avoid any small, bite-sized fish that the cardinalfish may prey on overnight and do not house with other cardinalfish species. As with many fish from the family Apogonidae, these large-eyed fish are active during the evening/night, and a period of blue moon lighting will enable you to observe their antics more closely after the main tank lights have been switched off. The bright yellow ocellus on the caudal peduncle is thought to confuse predators. May also be seen on sale as the Five-banded Cardinalfish or the Sharptooth Cardinalfish (alluding to the large canine-like teeth on both jaws).
Feeding
Offer a variety of meaty items such as Mysis shrimp, vitamin-enriched brineshrimp, finely chopped krill/cockle/clam meat etc. Feed small amounts 3 times per day, with at least one of the feeds after lights out.
Breeding
Five-lined Cardinalfish form distinct pairs during courtship and spawning, which tends to take place at night. The male fish will mouthbrood the egg mass until hatching. The larvae are then released into the water column, where they develop for some weeks before settling out of the plankton. Once released, there is no further parental care.
